Dynamo-electric machine.



A. H. NEULAND.

DYNAMO ELECTRIC MACHINE.

APPLICATION FILED FEB. 3. 1914.

Patented Oct. 19, 1915.

ma 5 vwe nboz ALFONS H. NEULAND, 0F BERGENFIELD, NEW JERSEY.

DYNAMIC-ELECTRIC MACHINE.

Specification of Letters Patent.

Patented Oct. 19, 1915.

Application filed February a, 1914. Serial No. 816,157.

To all whom it may concern:

Be it known that I, ALroNs H. NEULAND, a subject of the Czar of Russia, residing at Bergenfield, in the county of Bergen and State of New Jersey, have invented certain new and useful Improvements in Dynamo- Electric Machines, of which the following is a full, clear, and exact description.

My invention relates to dynamo-electric machines and particularly to dynamos of the variable speed type, and an object of my invention is to provide simple and reliable means for regulating the generated potential of such machines.

Another object is to provide means in combination with the potential regulator for closing the load circuit when a certain predeterminedipotential is developed.

Other objects and advantages of my invention will appear from the following description.

In accordance with my invention, I provide means for shunting from the armature part of the lines of force, the number which is diverted being proportional to the speed and to the potential developed in the armature. More specifically, a magnetic shunt member is provided which is adapted to form a closed magnetic shunt path for the flux, and which is normally held in nonshunting position by a retractile spring and is moved to shunting position by the force developed by a coil on the shunt member and acting on the field. In its preferred form, the shunt member is a rotatable member normally held by a spring in position with its poles in non-shunting position with respect to the field poles, but is adapted to be turned through an angle of 90 to short circuiting position, and to shunt more or less of the lines of force, depending upon its angular position. The shunt member is pro v vided with a winding energized by the current generated in the armature, which serves to produce a force acting on the field, thereby causing the shunt member to rotate in a predetermined direction from non-shunting position and .assume shunting position.

My invention also comprehcnds in combination with the movable shunt member, a circuit closer which is operated by the movement of the shunt member and closes the load circuit. The tension of the retractile means is so adjusted that it will maintain the shunt member in full non-shunting position until a predetermined speed is attained developing a predetermined voltage, which supplies the field coils and the coil on the shunt member with current. The magneto-motive forces of the field and shunt member are in quadrature to each other, thus producing a torque in one direction. A voltage in excess of this predetermined voltage will result in suflicient torque being developed to counteract the retractile force and turn the shunt member through an angular movement proportional to the excess volt age, and this movement results in the closure of the load circuit. To compensate for the sudden drop in potential which would result from this sudden closing of the load circuit, and thereby prevent the shunt memher from turning back and opening the load circuit, the dynamo is provided with a compound winding.

My invention also comprehends various other features of construction and arrange ments and combinations of parts, as will hereinafter more fully appear.

I shall now describe the embodiment of my invention illustrated in the accompanying drawings and shall thereafter point out my invention in claims.

Figure l is a transverse vertical section of a dynamo embodying my invention; Fig. 2 is a central longitudinal vertical section of the same, taken at right angles to that of Fig. 1; Fig. 3 is a detail in elevation of the circuit closing mechanism, as viewed from the left of Fig. 2; Fig. 4 is a diagram of the electrical circuits.

The illustrated dynamo electric machine is provided with a compound winding having the series winding 1 and the shunt winding 2 surrounding the yoke of the field poles 3 and 4, and an armature 5 rotatable between the faces of the poles 3 and 4. The dynamo belongs to thatclass known as variable speed dynamos in which the armature in operation is driven at variable speeds. The normal path for the flux is through the field poles and through the armature 5, and since with constant excitation the generated potential is directly pro portional to the speed of the armature, the potential will also be variable. In order to maintain the voltage at a constant after a predetermined maximum has been attained,

irrespective of the speeds of the armature in excess of that necessary to develop this upon the winding of the shunt member, and

thereafter it shunts an increasing number of lines of force as the speed of the armature increases beyond that critical speed, and substantially in proportion to the increase of armature speed, and thereby maintains the voltage constant.-

In the form illustrated the shunt member comprises a soft iron, flat body member 6 arranged between the field windings and the armature and rotatable upon an axis parallel to that of the armature. This body member is contained between two soft iron plates or heads 7 and 8, arranged longitudinally thereof along its narrow sides, and these heads or plates are joined together at their ends by brackets 9 and 9- of non-magnetic material which have hub portions in which are secured the trunnions 10 and 11 which bear in hubs in the side plates 12 and 13 of the dynamo. The heads or plates 7 and 8 are somewhat wider than the thickness of the body member 6 and they are transversely curved or ,convexed on their outer faces to the axis of the shunt member as acenter,with the result that the shunt member in cross-section is generally of a spool shape, as shown in Fig. 1. Opposite this shunt member the field poles 3 and 4 are provided with supplemental inward polar extensions 14 and 15, respectively, which serve as poles for the shunt member and have their faces concaved to the axis of the shunt member as a center, and the length of the diametral linesbetween their faces is such that the convex faces of the shunt member rotate in close proximity to the polar faces.

The shunt member is provided with a winding 16, which is energized by the current generated in the armature, and in the illustrated embodiment is connected in shunt therewith. This winding is arranged lengthwise around the body member 6 of the shunt member between the heads 7 'and 8, and between the ends of the body member 6 and the brackets 9 and 9, respectively. This shunt winding for the shunt member serves to produce a magneto-motive force in quadrature to that produced by the field poles, which causes the shunt member to rotate and assume a position with the heads 7 and 8 adjacent the poles 14 and 15, so as to afford a path for the excess of the magnetic flux.

The length of the faces of the intermediate poles 14 and 15 is such that when the shunt member is in a-vertical position or in a position at right angles to the poles 14 and 15, as shown in Fig. 1, the heads 7 and 8 are entirely outside of the poles 14 and 15, and in this position it is manifest that the least number of lines of force which constitute lines of leakage, are shunted from the armature through this shunt member. A slight angular movement of the shunt member, however, serves to bring the heads at the entrance to the field between the poles 14 and 15, in which position more lines of force are shunted, and it is evident that the further the heads rotate within the magnetic field the more lines of force will be shunted.

Means are provided to normally maintain the shunt member in its non-shunting position or position of minimum shunting effect, and these means in the form shown comprise a flat helical spring 17 which surrounds a hub 18 on the outer end of the trunnion 11, and is secured at one end to the hub and at the other end to the side face 13 of the'dynamo. Also secured to the hub 18 is an upwardlyextending arm 19 which is arranged to engage a stop 30 on the side plate 13, and the spring 17 normally holds the plate 19 angular movement will be directly proportional to this excessivetorque. Since this torque is produced by the magneto-motive force which is the result of the voltage generated in the armature and acting on the coil of the shunt member, this torque is directly proportional to the voltage in excess. of the predetermined maximum or critical voltage. and since this voltage is increased by the speed of the armature, it follows that the torque of the shunt member by reason of the increased current in the coil thereon is also increased by the speed of the armature in excess of that necessary for generating the v predetermined or critical voltage. It is to be noted that by these means the potential is kept substantially constant whether the armature carries a load current or not, and the regulation is practically independent of the armature reaction. This is directly due to the coil on the shunting member which 'causes it toproduce a torque in proportion to the voltage impressed upon the coil of the shunt member. This method of generatin a constant potential at varying speeds ofiers the further advantage of permitting separate and constant excitation from a battery, thus forcing the generator to pick up in- ?tantly in cases where the critical speed is The requisite torque for producing angular movement in the shunt member is not attained until the desired voltage is generated, which voltage is determined by the tension of the spring 17, and a slight excess over the predetermined voltage is necessary to cause the shunt member to turn and bring its heads within the field of the poles l4 and 15, and as the speed of the armature increases, the shunt member turns and shunts enough lines of force from the armature to substantially keep the voltage at the predetermined value, and the more the armature speeds up, the more the shunt member turns on its aXis and the more lines of force are shunted, and this equalizing action continues until the shunt member assumes a horizontal position or one at right angles to that shown in Fig. 1, which is its position of maximum shunting effect. In practice, however, the speed of the armature seldom, if ever, becomes sufiiciently great to cause the shunt member toassume this position.

The load or consuming circuit is also controlled by this shunt member in the construction shown, and is kept open until'the predetermined voltage is attained, and is then closed by the movement of the shunt member. In the illustrated embodiment, this is efiected by a movable contact member 20 which cooperates with a stationary contact member 21 in the consuming circuit, and which is carried on the lower end or" a freely swinging arm 22 which is pivoted at its upper end on a pivot pin 23 on the side plate 13 of the dynamo. A coiled spring 24 tends to swing the arm 22 so as to close this electrical contact, but in the normal position of the shunt member, this is prevented by the engagement of the arm 22 near its upper end against a pin 25 on the arm 19. As the arm 19 is moved with the shunt memher by the magneto-motive force, the arm 22 is permitted to follow it up under the influence of the spring 24, and but a very. slight movement is required to close the electrical contact in the consuming circuit. The sudden drop in potential caused by this closing of the load circuit is compensated for by the series winding 1 of the field poles, and the shunt member is thereby prevented from turning back and opening the load circuit. By these means the load circuit is kept open until the predetermined voltage is attained, and is then automatically. closed and kept closed. and the voltage in the load circuit is thereafter maintained substantially constant. The circuit closing mechanism may be .inclosed by a plate 26 secured to inwardlyprojecting ears on an annular flange 27 on the casing.

It is obvious that various modifications may be made in the construction shown in the drawings and above particularly described within the principle and scope of my invention.

I claim:

1. In a generator, the combination with a field magnet having armature poles and supplemental poles, and with an armature adapted to rotate at variable speeds between the armature poles and thereby to have a varying potential generated therein, of means for maintainin a substantially constant potential at varying speeds of the armature comprising a magnetic shunt member rotative between the supplemental poles in magnetic relation thereto and adapted in one position to shunt a minimum number of lines of force and in another position to shunt a maximum number of lines of force, and a winding on the shunt member fed by the varying potential and current from the armature, whereby the shunt member exerts a varying torque on the supplemental poles dependent upon the generated potential and tending to cause the shunt member to rotate to various shunting positions.

2. In a generator, the combination with a field magnet having armature poles and supplemental poles, and with an armature adapted to rotate at variable speeds between the armature poles and thereby to have a varying potential generated therein, of means for maintaining a substantially constant potential at varying speeds of the armature comprising a magnetic shunt member rotative between the supplemental poles in magnetic relation thereto and adapted in one position to shunt a minimum number of lines of force and in another position to shunt a maximum number of lines of force, a winding on the shunt member fed by the varying potential and current from the armature, whereby the shunt member exerts a varying torque on the supplemental poles dependent upon the generated potential and tending to cause the shunt member to rotate to various shunting positions, and retractile means arranged to restrain the shunt member against rotation until a predetermined potential is generated. I

3. In a generator, the combination with a field magnet having armature poles and supplemental poles, and with an armature adapted to rotate at variable speeds between the armature poles and thereby to have a varying potential generated therein, and with a consuming circuit, of means for maintaining a substantially constant potential at varying speeds of the armature comprising a magnetic shunt member rotative between the supplemental poles In magnetic relation thereto and adapted when at substantially right angles to the supplemental poles to shunt a minimum number of lines of force and when in line with the supplemental poles to shunt a maximum number of lines of force, retractile means adapted to hold the shunt memberin the position at substantially right angles to the supplemental poles and arranged to restrain the shunt member against rotation until a prepoles, and a controlling switch for the con-; 'suming circuit arranged to be closed by the shunt member as the shunt member moves to shunting position.

4. In a generator, the combination with a field magnet having compound windings and having armature poles and supplemental poles, and with an armature adapted to rotate at variable speeds between the armature poles and thereby to have a varying potential generated therein, and with a consuming circuit, means for maintaining a substantially constant potential at varying speeds of the armature comprising a magnetic shunt member rotative between the supplemental poles in magnetic relation thereto and adapted in one position to shunt a minimum number of lines of force and in another position to shunt a maximum number of lines of force, a winding on the shunt member fed by the varying potential and current from the armature, whereby the shunt member exerts a varying torque on the supplemental'poles dependent upon the generated potential and tending to cause the shunt member to rotate to various shunting positions, and a controlling switch for the consuming circuit arranged to be closed by the shunt member as the shunt member moves to shunting position, the compound winding preventing the retracting of the shunt member when the consuming circuit is closed.

In a'generator, the combination with a field magnet having compound windings and having armature poles and supplemental poles, and with an armature adapted to rotate at variable speeds between the armature poles and thereby to have a varying potential generated therein, and with a onsuming circuit, of means for maintaining a substantially constant potential at varying speds of the armature comprising a magnetic shunt member rotative between the supplemental poles in magnetic relation thereto and adapted when at substantially right angles to the supplemental poles to shunt a minimum number of lines of force and when in line with the supplemental poles to shunt a maximum number of lines of force, retractile means adapted to hold the shunt member in the position at substantially right angles to the supplemental poles and arranged to restrain the shunt member against rotation until a predetermined potential is generated, a winding on the shunt member fed by the varying potential and current from the armature, whereby the shunt member exerts a varying torque on the supplemental poles dependent upon the generated potential tending to cause the shunt member to rotate against the tension of the retractile means toward the position of alinement with the supplemental poles, and a controlling switch for the consuming circuit arranged to be closed by the shunt member as the shunt member moves to shunting position, the compound winding serving to prevent the retracting of the shunt member when the consuming circuit is closed.

6. In a variable speed generator, the combination with a potential regulator comprising a movable magnetic shunt member adapted in various positions to shunt more or less lines of force from the armature, and means carried by the shunt member and controlled by the generated potential in the armature for moving the shunt member into more or less eflective shunting position, of a circuit, closer for the external circuit arranged to be operated by the shunt member to close the circuit as the shunt member is moved from its least eiiective shunting position.

7. In a variable speed generator including a substantially constant magnetic field, the combination with a potential regulator comprising a movable magnetic shunt member adapted in various positions to shunt more or less lines of force from the armature, and with means carried by the shunt member and controlled bythe generated potential .in the armature for moving the shunt member into more or less effective shunting position, of a circuit closer for the external circuit arranged to be operated by the shunt member to close the circuit as the shunt member is moved from its least eiiective shunting position, and retractile means for the circuit closer arranged to restrain the circuit closer from operation until a prede termined potential is generated.

8. In a variable speed generator, the combination with a field magnet having compoundwindings and with the armature, of

a potential regulator comprising a movable magnetic shunt member adapted in various positions-to shunt more or less lines of force from the armature, means carried by the shunt member and controlled by the generated potential in the armature to move the shunt member into more or less eflective shunting position, a circuit closer for the external circuit arranged to be operated by the shunt member to close the circuit as the shunt member is moved from its least effective shunting position, and retractile means for the circuit closer arranged to restrain the circuit closer from operation until a predetermined potential is generated, the compound winding serving to prevent the retracting of the circuit closer when the external circuit is closed.

In witness whereof, I subscribe my signature, in the presence of two Witnesses.

ALFONS H. NEULAND. Witnesses:

VICTOR D. Bons'r, WALDO M. CHAPIN. 

